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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

35436 results found.

  1. GRB 021113: Optical Observations
  2. GRB 021113: Optical Observations
  3. GRB021113 (=H2449): A Long GRB Localized by HETE
  4. GRB 021112: Optical Observations
  5. GRB 021112: R-band search
  6. IPN triangulation of GRB021108 (large error box)
  7. GRB021112 (=H2448): A Long GRB Localized by HETE
  8. GRB 021016: Optical Observations
  9. IPN triangulation of GRB021109 (annulus)
  10. IPN triangulation of GRB021108 (annulus)
  11. IPN triangulation of GRB021104 (annulus)
  12. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  13. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  14. SGR1900+14 activity, November 2-4, 2002
  15. GRB021104: Candidate present in DSS
  16. IPN triangulation of GRB021102 (annulus)
  17. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  18. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  19. IPN triangulation of GRB021025 (portion of annulus)
  20. IPN triangulation of GRB021027 (single large error box)
  21. GRB021004, late-time optical observations
  22. IPN triangulation of GRB021027 (two large error boxes)
  23. GRB 021023: Infrared Imaging
  24. IPN triangulation of GRB021027 (annulus)
  25. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  26. IPN triangulation of GRB021025 (annulus)
  27. IPN triangulation of SGR1900+14, October 22 2002
  28. GRB 021004: optical observations
  29. IPN triangulation of GRB021023 (small error boc)
  30. GRB 020813; likely host galaxy.
  31. IPN triangulation of GRB021020 (smaller error box)
  32. IPN triangulation of GRB021020
  33. GRB 021008, radio observations
  34. GRB 021016, optical observations
  35. GRB 021004: VRI observations at TNG: possible break
  36. GRB021016, optical observations
  37. SGR1900+14: burst on October 10 2002
  38. GRB 021008, optical observations
  39. GRB021016(=H2397): A Long GRB Localized by HETE
  40. IPN triangulation of GRB021016 (small error box)
  41. IPN triangulation of GRB021014 (large error box)
  42. IPN triangulation of GRB021013 (single error box)
  43. GRB 021004: optical spectroscopy on Oct 11
  44. IPN triangulation of GRB021013 (two small error boxes)
  45. GRB021004: High-resolution optical spectroscopy
  46. IPN triangulation of GRB021013 (annulus)
  47. GRB021004, UBVRcIc field photometry update
  48. IPN triangulation of GRB021008 (single error box)
  49. GRB 021004 submm observations
  50. IPN triangulation of GRB021008B (annulus)
  51. IPN triangulation of GRB021008 (two small error boxes)
  52. GRB 021004: Optical/NIR Observations
  53. GRB 021004: Additional V-band Polarimetric Observations
  54. GRB021004: optical observation
  55. GRB 021004: Host Galaxy Star Formation Rate
  56. GRB 021004 submm observations
  57. GRB 021004: WC wind?
  58. IPN triangulation of GRB021008
  59. GRB 021004: Optical measurement at OHP
  60. GRB 021004: Optical observations, AUDE network
  61. GRB 021004 - VLA Radio Observations
  62. GRB 021004 - Unusual Radio-to-Submm Spectrum
  63. GRB 021004: optical spectroscopy
  64. IPN triangulation of GRB021007 (annulus)
  65. GRB 021004: HST/STIS spectroscopic observations
  66. GRB021004: optical observations and predicted break time
  67. GRB 021004 redshift
  68. GRB 021004: Optical Decay
  69. GRB 021004 continued IR fading
  70. HETE fluences for GRB021004
  71. GRB 021004, spectroscopic observations
  72. GRB021004: not fading anymore?
  73. GRB 021004: Optical Photometry at 2.5 Days
  74. GRB 021004: polarimetric observations
  75. GRB 021004: V-band Polarimetric Observations
  76. GRB 021004: Optical Decay
  77. GRB021004, astrometric position
  78. GRB021004, Optical Observations
  79. IRAM Millimeter detection of GRB 021004
  80. GRB 021004: Optical observations at RIKEN
  81. GRB 021004 radio observation
  82. GRB 021004: Optical Observations
  83. GRB021004: continued fading
  84. GRB 021004: Optical Photometry at 1.5 Days
  85. GRB021004, Optical Observations
  86. GRB021004, BVRcIc field photometry
  87. GRB 021004: Optical observations
  88. GRB 021004: optical counterpart
  89. GRB 021004, optical observations
  90. GRB021004: Optical Spectroscopy
  91. GRB 021004: Optical Observations
  92. GRB 021004, SPM optical observations
  93. GRB 021004, optical observations
  94. GRB 021004 radio search
  95. GRB 021004: radio observations
  96. GRB 021004: steepening of the optical decay slope
  97. GRB021004: Upper limits from recent and historical observations
  98. XRF020903, BVRI field photometry
  99. GRB021004: optical observations at Nyrola
  100. GRB021004: Absorption redshift

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